GEOLOGY AND PALEONTOLOGY OF THE CANAL ZONE. 459 



and three other specimens); 6868, Pope's Saddle, collected by 

 T. W. Vaughan. 



Type.— No. 325211, U.S.N.M. 



This coral may ultimately be shown to intergrade with Cyatho- 

 morplia Mlli. but according to the specimens available for study 

 they are distinct. 



Gyathomorpha browni is named for Prof. Amos P. Brown who paid 

 considerable attention to the paleontology of the Central American 

 and West Indian Tertiary formations. 



CYATHOMORPHA BELLI, new species. 



Plate 128, figs. 1, la, lb. 



Corallum more or less explanate, rounded above and flattish below; 

 base without epitheca, similar in this character to G. roclieitina. 



Calices large, 11.5 mm. a usual measure of the diameter, range in 

 diameter from 7.5 mm. (a small calice) to 12.5 mm.; distance apart 

 from 3.5 to 10.5 mm.; calicular rims elevated up to as much as 

 5 mm., usually lower on the distal than on the proximal side. Ca- 

 licular cavities relatively shallow in comparison with the diameter,, 

 depth about 2.5 mm. Corallite walls with few or no perforations 

 except at the upper edge; appear to be originally synapticulate and 

 subsequently compacted. 



Costae at the calicular edge subequal or slightly alternating in 

 size, corresponding to all septa; but just below the calicular edge 

 the costae corresponding to the last cycle of septa tend to decrease 

 in size and usually disappear at the base of the free corallite limb, 

 while the costae corresponding to the lower cycles of septa tend to 

 increase in height and extend as rather prominent plates on to or 

 even across the intercorallite areas. Costal edges with low beading. 



The septa in a calice 10 mm. in diameter are only 46 in number; in 

 another calice 9.25 by 13 mm. in diameter there are 48 septa. 

 Therefore, in comparison with the size of the calices, there are rel- 

 atively few septa, barely four cycles. In general the following is 

 the septal arrangement: primaries and secondaries extend to the 

 columella, and have a circle of single or double paliform lobes; 

 tertiaries extend to or almost to the columella, but are thinner 

 than the primaries and secondaries, and many bear a paliform lobe 

 near the columella; the quaternaries are shorter and thinner, some 

 of these bear pali. Over the mural summit the margins of all septa 

 are subequally slightly exsert, about 0.6 mm. is a maximum, average 

 between 0.25 and 0.5 mm. Large septa solid; higher cycles with 

 perforations. Septal arch a gradual curve. Margins with some 

 dentations. 



Columella large, about 3 mm. in diameter or nearly one-third the 

 diameter of the calice, trabecular, more or less whorled. 



